An example of a prior art engine mount is shown in FIG. 13. In this drawing, (A) is a front view, and (B) is a cross sectional view taken on line 13B-13B of (A). This engine mount 110 includes a first mounting metal fitting 120 on which an engine is mounted, a second mounting metal fitting 140 to be mounted on a vehicle body, and a vibration isolating elastic body 130 providing a connection between the first mounting metal fitting 120 and the second mounting metal fitting 140.
Herein, a reference character Z is a direction in which a static load of the engine is applied to the first mounting metal fitting 120, X and Y are two orthogonal directions in a plane orthogonal to the direction Z, and the Y direction of the X and Y directions is a direction extending along a mounting axis of the first mounting metal fitting 120.
An outside stopper 111 is provided around the first mounting metal fitting 120 in such a way as to enclose the latter in substantially an inverted U-shape. Each end bent to the second mounting metal fitting 140 side overlaps with the second mounting metal fitting 140 and is integrally combined therewith, so that the outside stopper 111 intersects at right angles to the Y direction and is arranged to extend in a long way in the X direction. The outside stopper 111 and the first mounting metal fitting 120 are connected by X direction elastic legs 135.
A vibration isolating elastic body 130 is made of rubber or the like and formed with Y direction elastic legs 133 which extend in the Y direction in a bifurcated form and the X direction elastic legs 135 which extend in the X direction in a bifurcated form. The Y direction elastic legs 133 are spaced apart from the X direction elastic legs 135 in the Z direction.
As shown in FIG. 13(A), the X direction elastic legs 135 extend in the X direction in a chevron shape in a front view. The first mounting metal fitting 120 is combined integral with a middle portion of the X direction elastic legs 135. Each end of the X direction elastic legs 135 is integrally joined to each lateral portion of the outside stopper 111.
As shown in FIG. 13(B), a projecting member 150 which extends downwardly from the fist mounting metal fitting 120 is inserted into and integrally combined with a middle portion of the Y direction elastic legs 133. Each end portion of the Y direction elastic legs 133 is joined to and integrally combined with vertical wall sections 141 provided in the second mounting metal fitting 140. The vertical wall sections 141 are formed in pairs in opposite positions located at each end in the Y direction of the second mounting metal fitting 140, and bent upwardly together with the second mounting metal fitting 140.
A space 134 is formed in such a way as to be surrounded by the vibration isolating elastic body 130, the second mounting metal fitting 140 and the outside stopper 111. This space 134 is closed in the X direction by lateral portions of the outside stopper 111, which are opposed in the X direction, and closed in the Y direction by the vertical wall sections 141 which are opposed in the Y direction.
With this construction, a spring constant is set up by the X direction elastic legs 135 between the first mounting metal fitting 129 and the outside stopper 111, and the deformation in the X direction of the first mounting metal fitting 120 is able to be regulated by the outside stopper 111.
Further, when the first mounting metal fitting 120 and the projecting member 150 move in the Y direction, the Y direction elastic legs 133 are compressed between the vertical wall section 141 and the projecting member 150. Therefore, a spring constant in the Y direction on the side of the Y direction elastic legs 133 can be increased to a certain extent. If there are no vertical wall sections 141, the elastic legs 133 are subject mainly to the shear deformation, and the spring constant in the Y direction is decreased remarkably.